Are Apple and Amazon the new Sharks and Jets of the tablet world?

Amazon's Kindle line of tablets is more reminiscent of Apple's iPad lineup than other Android devices - with everything from the hardware to the app store controlled by a single company.

Although they're technically powered by Android, Kindles are almost never lumped into the category of "Android" with Samsung, HTC and Motorola products. The devices use a heavily modified version of Android, and include many Amazon-specific features.

With the release of the iPad mini, Apple and Amazon are now competing in both the 7-inch and 10-inch tablet markets. So how do they stack up to each other, both in terms of individual devices and overall ecosystems?

One of the first things to note is the disparity between the apps and media available on each platform. Apple has far more apps available - more than 700,000 at last count, with 250,000 designed specifically for tablets, compared to just under 60,000 for Amazon. And while that superiority is less clear-cut where available media is concerned, Apple still has the advantage - with 26 million songs to Amazon's 20 million, and 235,000 movies and TV episodes to Amazon's 120,000.

Apple's also ahead of Amazon in the large-tablet market, with this week's release of a new full-sized iPad just seven months after the third-generation model. The fourth-generation iPad boasts a bigger, more impressive display than the Kindle Fire HD 8.9, powered by an advanced new A6X system-on-a-chip that should provide top-end performance. However, the more powerful iPad will set you back at least $100 more than a comparably equipped 8.9.

The iPad mini doesn't have the same superiority over the 7-inch Kindle Fire HD, however. Leaving aside Apple's aforementioned advantages in terms of apps and media, the Kindle Fire HD offers a far more attractive value proposition, at just $200 for a system that's at least as technologically impressive as the $329 mini with the same 16GB storage capability. The iPad mini's internal components are more or less the same. (Note that the listed prices for the Kindle Fire lineup are for the subsidized versions, which show ads on the lock screen and home screen. Ad-free versions are available for $15 more.)

This discrepancy gets to the heart of Amazon's central advantage against Apple - cost. Kindle Fire HD models are cheaper than their iPad equivalents across the board, often by substantial amounts. A 32GB Kindle Fire HD 8.9-incher with 4G costs $499, while an iPad with 4G and the same amount of storage costs $729.

However, Apple's technical advantages, mature app ecosystem and well-known stylishness may justify the extra money for a lot of buyers. At the high end, it's tough to argue that the fourth-gen iPad isn't the new standard for full-size tablets, which likely makes it at least partially worth its premium price. The picture's less clear at the low end, however, as the iPad mini's surprisingly dated hardware makes it more difficult to justify the mark-up.